This invention relates to a door locking mechanism and more particularly to a door locking mechanism for use on either an inwardly or outwardly opening door which can be locked and unlocked from the outside.
Commercial establishments and many residential buildings in urban areas require door locking mechanisms with improved ability to withstand attempts at unlawful entry.
In my U.S. Pat. No. 4,796,445 I disclose a door locking mechanism designed to be used on outswinging doors being capable of being locked in both the open and unclosed positions, an important aspect for a door being used to meet fire regulations where the public will or may congregate such as public halls, restaurants, theaters, and the like.
For commercial and residential buildings not designed to meet the fire regulations for crowds of people, there is the need for a door locking mechanism economical in construction with the ability to secure a door on both sides to improve the capability to resist breaking and entering and also to permit entry from the outside. Also, the door locking mechanism should be trouble free in operation and capable of use on both inwardly and outwardly opening doors.
In a police action door lock marketed by Vigilante Burglar Bars. Inc., there is employed a lever operated double throw door locking mechanism which can only be used in outwardly swinging doors and can not be locked and unlocked from the outside. In addition, the pivoting arrangement requires that the angle of the bars being extended varies over their range of movement thereby rendering it difficult if not impossible to make a tight fit on the door jamb if a female receiving member is employed.
In the Fox Police Double Bolt Lock, a worm and gear arrangement is employed in which the spindle and tailpiece may become locked in position and thus is not trouble free. Another problem with this construction is the cost of a worm and gear arrangement. It is also not clear whether the arrangement can be conveniently employed with an inwardly opening door.